Format PC/MacDeveloper Mike Bithell with music from David HousdenReleased Out now

Chris is my favourite. Thomas might be my namesake, but I feel like Chris and I share a lot in common. We're both short, squat, irrepressibly grumpy and harbour a deep-seated resentment towards those that are taller, thinner and can jump higher than us. Gits. Me and Chris are also both hopeless romantics... aw.

The thing with Chris though, is that he's a square. Not figuratively either, an actual square. A little orange one. I'm relating to a fictional, geometric shape on a screen. It's a new sensation for me, but a very real one. One that does make you wonder if all those video games do make you go a bit floopy after all.

But it's not that. Instead it's a fascinating example of great writing being able to stir the imagination, building personality out of the simplest visual tools and sharp language. Each quadrilateral character in Thomas Was Alone has its own worries and traits, narrated with real delight, wit and verve by Danny Wallace. And David Housden's wonderful, understated score lays down an irresistible aural backdrop to the basic but beautiful visuals.

Thomas Was Alone's minimalist appearance is not a barrier, but a launch pad.The best 'indie' games make a virtue of the limitations put upon them by resource and technology. That's exactly what developer Mike Bithell has done with Thomas, crafting a charming, sharp and smart puzzle-platformer.

The basic set-up is that Thomas, a small, red rectangle, is an AI program that is part of a larger system. The creators of the AI had no idea that Thomas would develop such a personality of his own, that of a curious, excitable type ready for adventure. Thomas discovers portals within his system, and after learning how to jump --or 'inverted fall' as he calls it-- makes his way through each portal to find out what's on the other side. Your job is to guide Thomas through each self-contained level to the portal. But it's not long before he is joined by veritable platoon of all shapes and sizes, all with their own skills.

Chris is first, with the grumpy bugger immediately taking a dislike to the stupidly chirpy Thomas. Chris can't jump very high, but he can squeeze through tight spaces, and give Thomas a boost so he can jump a bit higher (as you can imagine, Chris doesn't like this much at all). John is a lanky, yellow rectangle that can leap high into the air (and doesn't he like to show off about it). Claire is a giant blue square whose ability to float in water makes her believe she's a superhero. While Laura is a horizontal pink rectangle who can spring other shapes from her bouncy midriff. As any girl-rectangle-person would, she develops a bit of a complex about this, wondering if her companions are just using her for her trampoline-aping frame.

You can switch between the characters at the press of a button, leading them to the exit of each stage, working together to reach the portal. Chris may need to slip through a small gap to push a button, but his lack of mobility means that the others may have to form a staircase so he can hop up to the next platform (how embarrassing). There's a lot of clever design work that goes into the 2D levels. Most aren't too taxing, but having the group interacting with each other gives the solutions a sense of real pleasure. There's something strangely satisfying about how each character glides across the environment at their own pace too. However, there can be a certain element of awkwardness in switching the characters at pace, exacerbated by the occasional repeat puzzle. The staircase move, for example, is a delight the first time you use it, but having to repeat it several times can feel a little too much like busywork. Thomas overcomes this foible with the personalities of the blocks, with you imagining them huffing and puffing as they clamber over each other to reach the next platform.

There's a distinct sense of momentum to the narrative that dictates the introduction of new characters and challenges. Story and mechanics are one and the same here, gently riffing off each other to keep you engaged if the pace of either starts to sag. The game pushes you on because, like our protagonist, you want to know what's through the next portal -- another companion maybe, or a clever twist on the mechanics. And while Thomas can sometimes be a little slow in showing its hand, when it does so it rarely fails to raise a smile. There's a cheekiness there too, lulling you into thinking you've seen all the game has to offer before it dramatically widens its reach. Towards the end, Thomas ropes in all of its elements to form something quite brilliant, let down only by a nagging lack of precision in the controls.

Fiddly bits notwithstanding, Thomas Was Alone is a game crafted with real love and attention. It shines through most prominently in its neurotic set of blocks, a cast so delightful you'd give them a cuddle if they weren't all sharp edges. Mind you, I'm not sure Chris would like that too much. But even that grumpy old square would admit that spending time with Thomas is, actually, a whole lot of fun.